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arXiv · 1012.0407

Anomalous Josephson current via Majorana bound states in topological insulators

P. A. Ioselevich·M. V. Feigel'man
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Abstract

We propose a setup involving Majorana bound states (MBS) hosted by a vortex on a superconducting surface of a 3D Topological Insulator (TI). We consider a narrow channel drilled across a TI slab with both sides covered by s-wave superconductor. In the presence of a vortex pinned to such a channel, it acts as a ballistic nanowire connecting the superconducting surfaces, with a pair of MBS localized in it. The energies of the MBS possess a 4π-periodic dependence on the superconductive phase difference ϕbetween the surfaces. It results in the appearence of an anomalous term in the current-phase relation, I_a(ϕ) for the supercurrent flowing along the channel between the superconductive surfaces. We have calculated the shape of the 4π-periodic function I_a(ϕ), as well as the dependence of its amplitude on temperature and system parameters.

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P. A. Ioselevich, M. V. Feigel'man. 2010-12-02. Anomalous Josephson current via Majorana bound states in topological insulators. https://doi.org/10.1103/physrevlett.106.077003

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